Go through the hole in the wall ahead of you and turn left just past the hole and down a bit for the Collectible.

Aim your reticule at the guard, when it turns red, fire at him. Watch his red life bar -- Spencer will say something stupid when he's dead. There's another soldier in the next room. In the corner of this room is ammunition.

Now's a good time to learn some Evade skills. Roll past the clump of guards with the Evade button held.

Collectible 2

Go up the stairs and look to the right for the Collectible.

Shoot the three enemies below from your vantage point above them. Reorient around the hole for a better angle if you need it.

Collectible 3

Drop down and search the room for this Collectible.

Look down the hallway while zooming and kill the soldier at the end for the Close Up Challenge.

Collectible 4

Head down the hallway and, at the end, collect the Collectible.

Collectible 5

Go down the stairs and use your zoom to kill the grunts while peeking around the corner. You'll now cross another long sky bridge / hallway. At the end is Collectible 5.